Resilient distributor connector



Oct. 8, 1957 F. s. SLICK RESILIENT DISTRIB UTOR CONNECTOR Filed March 15, 1954 FEE! 5. Eliflk United States Patent T RESILIENT DISTRIBUTOR CONNECTOR Fred S. Slick, Rockford, Ill., assignor to J. I. Case Cornpany, Racine, Wis., a corporation of Wisconsin Application March 15, 1954, Serial No. 416,095

3 Claims. (Cl. 339-100) This invention relates to connectors for connecting ignition cables to distributor heads and magnetos on automobiles and other internal combustion engine systems.

This invention specifically relates to a resilient connector intended to prevent interruption in the circuit between the distributor head or magneto and the spark plugs of the engine. Som vibration usually attends the operation of internal combustion engines, and frequently results in the loosening of the electrical connections. Loose connections may interrupt the system only momentarily or could break the circuit completely. The interruption may not be evident upon a casual inspection and frequently causes delay until found. The most troublesome of these interruptions happens when a wire from the spark plug to the distributor becomes loose from the latter.

The present invention assures a positive connection by use of a resilient member attached to the end of the cable and fitted to a cavity in the distributor head. This connector is effective to maintain a positive contact during excessive vibration, and requires only a pushing of the connector end of the wire into the cavity provided for the purpose when making the connection, and merely pulling the wire out when breaking the contact. The gist of this invention is the resilient connector portion.

The accompanying drawing illustrates the best mode presently contemplated by the inventor for carrying out the invention.

Referring to the drawing:

Fig. l is an enlarged fragmentary view of a distributor cap of the type used on some internal combustion engines and embracing the invention.

Fig. 2 is a plan view of a fragmentary portion of Fig. 1 taken at 2-2 of Fig. 1.

Fig. 3 is an enlarged end view of the invention, and

Fig. 4 is an enlarged fragmentary view taken at 44 of Fig. 3.

Referring to Fig. l, is a conventional distributor head of the type used in the ignition systems of many internal combustion engines. terminal bosses E2; in this instance four are required in that the distributor is designed for a four-cylinder engine.

Each boss 12 comprises a terminal cavity 14 which has a contact disk 16 molded or pressed into the head permanently. A brush 18 and spring 29 are assembled in a cavity 22 beneath the disk 16 for purposes not relating to this invention, so they will not be further described.

A set of cables 24 extend from the distributor head It? to the spark plugs. As each wire is similarly connected to the head 10, the description will be confined to only one. Cable 24 extends freely into cavity 14 and to a distance substantially as shown in Fig. l, and is of the stranded type made of a group of small wires 26 having a rubber cover and a plastic coated exterior surface. The end 28 of the cable 24 is cut off squarely for reasons that will appear.

The gist of the invention is the provision of a helical Head 10 is provided with l 2,809,359 Patented Oct. 8, 1957 spring 30 made of Phosphor bronze or other suitablematerial having the required resiliency, and comprises a series of coils such as 32 of varying diameters to permit the smaller coils to telescope within the larger coils when the spring 36 is compressed. This construction is an assurance that the coils will not contact each other so that a resilient connection will always be established between the coils 32 and the disk 16.

The largest coil 34- of spring 30 is of a diameter slightly larger than the bore of cavity 14 which relationship compels coil 34 to contract in diameter when spring 30 is inserted in the cavity 14, thus creating a friction fit between the cavity and the coil 34.

In this instance, spring 30 terminates in a pair of coils 36 and 38 of considerably reduced diameter. The inner diameter of coils 36 and 38 are sufficient to permit a drive screw or self-tapping screw 40 to be inserted in the coils 36 and 48. Screw 49 is of the type having a tapered threaded portion 42 which is capable of cutting its own thread and is provided with a slotted head 44 for the reception of a screwdriver.

When applying this invention to a cable such as shown in Fig. 4, screw 4t) is inserted in coils 36 and 38, and with the aid of a screw driver, threads 42 are forced between wires 26 by turning the screw 40 inwardly until coil 38 contacts the end of wire 26. Thus wires 26 will diverge as indicated at 46, and threads 42 of screw 40 will imbed themselves into the wires 26.

The divergent portion in forms a seat for coil 38 thereby establishing a good electrical connection so that current can flow uninterruptedly through the spring 30 and to the disk 16.

When inserting wire 24 which has been assembled with spring 30 into cavity 14, coil 34 will be compressed slightly in diameter. When the end coil 32 contacts disk 16, a positive electrical contact will be made between the wire 26 and the disk 16. A force slightly in excess of that required to contact disk 16 will assure contact by compressing the coils of spring 30. Within certain limits, coil 34 will maintain the initial pressure on disk 16. Any excess pressure on disk 15 will result in coil 34 moving away from the disk until coil 34 comes to rest. The contact pressure on disk 16 will remain substantially uniform during vibration and there will be no tendency for the contact to be broken. The cable 24 can be removed by simply pulling the wire from cavity 14.

Various modes of carrying out the invention may be employed within the scope of the accompanying claims, which particularly point out and distinctly set forth the subject matter regarded as the invention.

I claim:

1. In a distributor head having a cylindrical connector cavity provided with a smooth, uninterrupted non-conducting surface and a contact member at the bottom thereof, a connector means for an electrical conductor comprisin a bulbous helical spring having a median coil of a diameter in excess of the diameter of said cavity, said spring having progressively-smaller coils spaced axially in both directions from said median coil, said progressively-smaller coils being of diameters so as to permit succeeding coils to nest within each other upon compressing said spring axially, one terminal coil of said spring secured to said conductor in electrical contact therewith and the other terminal coil resiliently contacting said contact member.

2. In a distributor head having a cylindrical connector cavity provided with an uninterrupted, non-conducting surface and a contact member at the bottom thereof, a connector means for an electrical conductor comprising a bulbous helical spring having a median coil of a diameter to frictionally engage said cavity, said spring having progressively-smaller coils spaced axially in both directions from said median coil, said progressively-smaller coils being of diameters so as to permit succeeding coils to nest within each other upon compressing said'spririg axially, one terminal coil of said spring secured to said conductor in electrical contact therewith and the other terminal coil resiliently contacting said contact member.

3. In a distributor head having a connector cavity provided with a smooth uninterrupted, non-conducting surface and a contact member at the bottom thereof, a connector means for an electrical conductor comprising a bulbous helical spring having a coil of a diameter to frictionally engage said cavity, said spring having progressively-smaller coils spaced axially in both directions from said median coil and being of diameters so as to permit succeeding coils to nest within each other upon compressing said spring axially, one terminal coil of said spring making contact with said conductor and the other terminal coil contacting said contact member.

References Cited in the file of this patent UNITED STATES PATENTS 1,933,304 Bell Oct. 31, 1933 2,183,696 Rohde Dec. 19, 1939 2,313,775 Scott Mar. 16, 1943 2,644,883 Schoenherr July 7, 1953 

